Photonic bandgap engineering in hybrid one-dimensional photonic crystals containing all-dielectric elliptical metamaterials.

Abstract

Metamaterials with negative permittivities or/and permeabilities greatly enrich photonic bandgap (PBG) engineering in one-dimensional (1-D) photonic crystals (PhCs). Nevertheless, their inevitable optical losses strongly destroy the crucial prohibition characteristic of PBGs, which makes such engineered PBGs not utilizable in some relevant physical processes and optical/optoelectronic devices. Herein, we bridge a link between 1-D PhCs and all-dielectric loss-free metamaterials and propose a hybrid 1-D PhC containing all-dielectric elliptical metamaterials to engineer angle-dependence of PBGs. Associating the Bragg scattering theory with the iso-frequency curve analysis, an analytical model is established to precisely describe the angle-dependence of PBG. Based on the analytical model, two types of special PBGs, i.e., angle-insensitive and angle-sensitive PBGs, are designed. By further introducing defects into the designed 1-D PhCs, angle-dependence of defect modes can also be flexibly controlled. Our protocol opens a viable route to precisely engineering PBGs and promotes the development of PBG-based physics and applications.